RESOURCE MANAGEMENT IB Computer Science HL Topics 1

RESOURCE MANAGEMENT IB Computer Science

HL Topics 1 -7, D 1 -4 1: System design 2: Computer Organisation 3: Networks 4: Computational thinking 5: Abstract data structures 6: Resource management 7: Control D: OOP

HL only 6 Overview Systemresources 1. Identify the resources that need to be managed within a computer system 2. Evaluate the resources available in a variety of computer systems 1: System design 2: Computer Organisation 3: Networks 3. Identify the limitations of a range of resources in a specified computer system 4. Describe the possible problems resulting from the limitations in the resources in a computer system 4: Computational thinking Role of the operating system 5. Explain the role of the operating system in terms of managing memory, peripherals and hardware interfaces 6. 1. 7 Outline OS resource management techniques: scheduling, policies, multitasking, virtual memory, paging, interrupt, polling 8. Discuss the advantages of producing a dedicated operating system for a device 5: Abstract data structures 6: Resource management 9. Outline how an operating system hides the complexity of the hardware from users and applications 7: Control D: OOP

Topic 6. 1. 9 ◦ Outline how an operating system hides the complexity of the hardware from users and applications

Teacher’s note • Students should be aware of a range of examples where operating systems virtualize real devices, such as drive letters, virtual memory, input devices, the Java virtual machine. • The issue of localization causing compatibility problems between systems in different countries is also important.

Abstraction leads to simplicity • Users and applications do not see the hardware directly, but view it through the OS. • This is used to hide certain hardware details from users and applications (called abstraction). • Due to this abstraction, users cannot see changes in the hardware. Can be used is to make related devices appear the same from the user’s point of view. • For example, hard disks, floppy disks, CD-ROMs, and USB keys are all very different media, but in many OSes they appear the same to the user.

Drive letters • A ‘drive letter; is a single alphabetic character A through Z that has been assigned to a physical drive or drive partition in the computer. • For example, a computer with a floppy drive has a drive letter of A: assigned to the drive. • All computers with a hard drive will always have that default hard drive assigned to a C: drive letter • CD-ROM or other drive is the next drive letter (e. g. D: ) etc.

Java Virtual Machine • A Java virtual machine (JVM interprets compiled Java binary code (called bytecode) for a computer's processor (or "hardware platform") so that it can perform a Java program's instructions. • Each platform gets its own JVM so that Java code ◦ can run on any platform.